I need help with science:

Which of the following explanations is correct about the wave that travels through the medium?

The correct answer is letter A

5 0

3 years ago

A force of 20N changes the position of a body. If mass of the body is 2kg, find the acceleration produced in the body.2. A ball

shepuryov [24]

Explanation:

Hello there!!!

You just need to use simple formula for force and momentum, 

F= m.a

and momentum (p)= m.v

where m= mass

v= velocity.

a= acceleration .

And the solutions are in pictures. 

Hope it helps..

5 0

3 years ago

Researcher measures the thickness of a layer of benzene (n = 1.50) floating on water by shining monochromatic light onto the fil

earnstyle [38]

Answer:

Minimum thickness; t = 9.75 x 10^(-8) m

Explanation:

We are given;

Wavelength of light;λ = 585 nm = 585 x 10^(-9)m

Refractive index of benzene;n = 1.5

Now, let's calculate the wavelength of the film;

Wavelength of film;λ_film = Wavelength of light/Refractive index of benzene

Thus; λ_film = 585 x 10^(-9)/1.5

λ_film = 39 x 10^(-8) m

Now, to find the thickness, we'll use the formula;

2t = ½m(λ_film)

Where;

t is the thickness of the film

m is an integer which we will take as 1

Thus;

2t = ½ x 1 x 39 x 10^(-8)

2t = 19.5 x 10^(-8)

Divide both sides by 2 to give;

t = 9.75 x 10^(-8) m

8 0

3 years ago

*PHYSICS HELP*

sveta [45]

My calculator is about 1cm thick, 7cm wide, and 13cm long.

Its volume is (length) (width) (thick) = (13 x 7 x 1) = 91 cm³ .

The question wants me to assume that the density of my calculator
is about the same as the density of water. That doesn't seem right
to me. I could check it easily. All I have to do is put my calculator
into water, watch to see if sinks or floats, and how enthusiastically.
I won't do that. I'll accept the assumption.

If its density is actually 1 g/cm³, then its mass is about 91 grams.

The choices of answers confused me at first, until I realized that
the choices are actually 1g, 10² g, 10⁴ g, and 10⁶ g.

My result of 91 grams is about 100 grams ... about 10² grams.

Your results could be different.

3 0

3 years ago

According to the momentum principle, the change in momentum of an object equals the impulse, which depends on______

3241004551 [841]

Answer: The momentum principle depends on MASS and VELOCITY.

Explanation:

The momentum principle states that net force changes the the momentum of an object where momentum is the product of the MASS of the body and it's VELOCITY.

Thus, momentum = mass(kg) ×velocity( m/s)= kgm/s ( derived unit)

Also to determine the rate of change of momentum;

Mass=m, initial velocity =u, final velocity = V and time =t

Initial momentum = mu

Final momentum = mv

Change in momentum = mv - mu

= m( v- u)

Rate of change of momentum=

m( v -u)/t --> equation 1

But V = u + at

Hence, a = v -u/t

Substitute for v -u/ t in equation 1

F = Kma, where k is constant and has the value of 1.

Therefore F = ma

Newton is the SI unit if force. It is defined as the force which gives a mass of 1kg an acceleration of 1 m/s².

IMPULSE is defined as the change of momentum of a body (mv-mu) or the product of force and time.

Thus impulse = force × time = m (v-u)

The unit is Ns ( Newton seconds) which is the same as change in momentum.

3 0

3 years ago